================ Running Gunicorn ================ .. highlight:: bash You can run Gunicorn by using commands or integrate with popular frameworks like Django, Pyramid, or TurboGears. For deploying Gunicorn in production see :doc:`deploy`. Commands ======== After installing Gunicorn you will have access to the command line script ``gunicorn``. .. _gunicorn-cmd: gunicorn -------- Basic usage:: $ gunicorn [OPTIONS] [WSGI_APP] Where ``WSGI_APP`` is of the pattern ``$(MODULE_NAME):$(VARIABLE_NAME)``. The module name can be a full dotted path. The variable name refers to a WSGI callable that should be found in the specified module. .. versionchanged:: 20.1.0 ``WSGI_APP`` is optional if it is defined in a :ref:`config` file. Example with the test app: .. code-block:: python def app(environ, start_response): """Simplest possible application object""" data = b'Hello, World!\n' status = '200 OK' response_headers = [ ('Content-type', 'text/plain'), ('Content-Length', str(len(data))) ] start_response(status, response_headers) return iter([data]) You can now run the app with the following command: .. code-block:: text $ gunicorn --workers=2 test:app The variable name can also be a function call. In that case the name will be imported from the module, then called to get the application object. This is commonly referred to as the "application factory" pattern. .. code-block:: python def create_app(): app = FrameworkApp() ... return app .. code-block:: text $ gunicorn --workers=2 'test:create_app()' Positional and keyword arguments can also be passed, but it is recommended to load configuration from environment variables rather than the command line. Commonly Used Arguments ^^^^^^^^^^^^^^^^^^^^^^^ * ``-c CONFIG, --config=CONFIG`` - Specify a config file in the form ``$(PATH)``, ``file:$(PATH)``, or ``python:$(MODULE_NAME)``. * ``-b BIND, --bind=BIND`` - Specify a server socket to bind. Server sockets can be any of ``$(HOST)``, ``$(HOST):$(PORT)``, ``fd://$(FD)``, or ``unix:$(PATH)``. An IP is a valid ``$(HOST)``. * ``-w WORKERS, --workers=WORKERS`` - The number of worker processes. This number should generally be between 2-4 workers per core in the server. Check the :ref:`faq` for ideas on tuning this parameter. * ``-k WORKERCLASS, --worker-class=WORKERCLASS`` - The type of worker process to run. You'll definitely want to read the production page for the implications of this parameter. You can set this to ``$(NAME)`` where ``$(NAME)`` is one of ``sync``, ``eventlet``, ``gevent``, ``tornado``, ``gthread``. ``sync`` is the default. See the :ref:`worker-class` documentation for more information. * ``-n APP_NAME, --name=APP_NAME`` - If setproctitle_ is installed you can adjust the name of Gunicorn process as they appear in the process system table (which affects tools like ``ps`` and ``top``). Settings can be specified by using environment variable :ref:`GUNICORN_CMD_ARGS `. See :ref:`configuration` and :ref:`settings` for detailed usage. .. _setproctitle: https://pypi.python.org/pypi/setproctitle Integration =========== Gunicorn also provides integration for Django and Paste Deploy applications. Django ------ Gunicorn will look for a WSGI callable named ``application`` if not specified. So for a typical Django project, invoking Gunicorn would look like:: $ gunicorn myproject.wsgi .. note:: This requires that your project be on the Python path; the simplest way to ensure that is to run this command from the same directory as your ``manage.py`` file. You can use the `--env `_ option to set the path to load the settings. In case you need it you can also add your application path to ``PYTHONPATH`` using the `--pythonpath `_ option:: $ gunicorn --env DJANGO_SETTINGS_MODULE=myproject.settings myproject.wsgi Paste Deployment ---------------- Frameworks such as Pyramid and Turbogears are typically configured using Paste Deployment configuration files. If you would like to use these files with Gunicorn, there are two approaches. As a server runner, Gunicorn can serve your application using the commands from your framework, such as ``pserve`` or ``gearbox``. To use Gunicorn with these commands, specify it as a server in your configuration file: .. code-block:: ini [server:main] use = egg:gunicorn#main host = 127.0.0.1 port = 8080 workers = 3 This approach is the quickest way to get started with Gunicorn, but there are some limitations. Gunicorn will have no control over how the application is loaded, so settings such as reload_ will have no effect and Gunicorn will be unable to hot upgrade a running application. Using the daemon_ option may confuse your command line tool. Instead, use the built-in support for these features provided by that tool. For example, run ``pserve --reload`` instead of specifying ``reload = True`` in the server configuration block. For advanced configuration of Gunicorn, such as `Server Hooks`_ specifying a Gunicorn configuration file using the ``config`` key is supported. To use the full power of Gunicorn's reloading and hot code upgrades, use the `paste option`_ to run your application instead. When used this way, Gunicorn will use the application defined by the PasteDeploy configuration file, but Gunicorn will not use any server configuration defined in the file. Instead, `configure gunicorn`_. For example:: $ gunicorn --paste development.ini -b :8080 --chdir /path/to/project Or use a different application:: $ gunicorn --paste development.ini#admin -b :8080 --chdir /path/to/project With both approaches, Gunicorn will use any loggers section found in Paste Deployment configuration file, unless instructed otherwise by specifying additional `logging settings`_. .. _reload: http://docs.gunicorn.org/en/latest/settings.html#reload .. _daemon: http://docs.gunicorn.org/en/latest/settings.html#daemon .. _Server Hooks: http://docs.gunicorn.org/en/latest/settings.html#server-hooks .. _paste option: http://docs.gunicorn.org/en/latest/settings.html#paste .. _configure gunicorn: http://docs.gunicorn.org/en/latest/configure.html .. _logging settings: http://docs.gunicorn.org/en/latest/settings.html#logging